In this specification where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.
According to the American Diabetes Association, diabetes is the fifth-deadliest disease in the United States. Since 1987 the death rate due to diabetes has increased by 45 percent. There are an estimated 20.8 million children and adults in the United States, or 7% of the population, who have diabetes. The total annual economic cost of diabetes in 2007 was estimated to be $174 billion. This is an increase of $42 billion since 2002. This 32% increase means the dollar amount has risen over $8 billion each year.
A critical component in managing diabetes is frequent blood glucose monitoring. Currently, a number of systems exist for self-monitoring by the patient. Most fluid analysis systems, such as systems for analyzing a sample of blood for glucose content, comprise multiple separate components such as separate lancing, transport, and quantification portions. These systems are bulky, and often confusing and complicated for the user.
As a result, certain efforts have been made to develop an “integrated device” that combines the steps and mechanisms for acquiring a sample body fluid, transporting the body fluid to a measurement device, and quantifying the level of analyte contained in the sample body fluid all in a single device. Examples of such devices are illustrated in U.S. Pat. Nos. 6,540,675 and 7,004,928. Although such devices are designed to reliably obtain an adequate sample volume from the user, occasionally, for a number of different reasons, the device will be unable to successfully collect and transport an adequate sample volume for analysis on a first attempt. Devices such as those described above include a skin-penetration member, such as a needle which is driven into the surface of the skin of the user. Once the skin-penetration member has been triggered or activated, such devices typically lack the ability to be “re-cocked” so that the same skin-penetration member can be used again to pierce the surface of the skin. When an inadequate sample volume is collected and transported as a result of the initial wound creation, that particular test cannot proceed. Thus, the test is “wasted.” The user must perform a new test using a fresh skin-penetration member and quantification member. This can increase the costs to the user associated with monitoring the analyte or glucose levels. Moreover, the inability to salvage a successful test from a single wound means that the user will often create a separate wound at a new sampling site, or be forced to cause further damage to the existing wound in order to collect and transport an adequate sample volume for analysis. This obviously increases the pain and frustration experienced by the user, which is counterproductive to the goal of encouraging the user to frequently and systematically monitor their analyte or glucose levels.
Therefore, there is a need in the art for providing body fluid sampling and analysis techniques and devices which offer the user greater flexibility in the collection of an adequate sample volume to present to the device for analysis.